The primary structure of a nucleic acid or protein is the sequence of bases or amino acids in the polynucleotide or polypeptide.
DNA
primary structure is the sequence of nucleotides of the nucleic acid. DNA contains a 5-carbon sugar (2' deoxyribose), a phosphate group, and a basic group on the 1'-carbon (cytosine, guanine, adenine, or thymine).
The linkage that connects the nucleotide monomers in nucleic acid is called the phosphodiester link. It connects successive monomers through a phosphate residue attached to the hydroxyl on the 5'-carbon of one unit and the 3'-hydroxyl of the next one. Thus, the chain has directionality (5'® 3').
The main importance of primary structure is that the genetic information is stored in the primary structure of DNA.
Proteins
The primary structure of a protein is the sequence of amino acids in the polynucleotides or peptide. Amino acids are coded for during translation. An amino acid is characterized by having a carboxyl group, amino group, and a side chain. The amino group and side chain are attached to the a -carbon. Hence the name a -amino acids.
Amino acids can be covalently linked by formation of a peptide bond by elimination of a water molecule to form a polypeptide. The N-terminal end contains an unreacted amino group and the C-terminal end contains an unreacted carboxyl group.
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Secondary Structure
Tertiary and Quaternary Structure
Sickle-Cell Anemia
Biotechnology
